A client looking to design an advertising campaign for a new off-road vehicle wishes to know, in a hurry, what percentage of car owners have ever thought about buying a 4-wheel drive vehicle. He/she calls a supplier running a motoring Omnibus on Wednesday and submits two questions:

• 'Have you ever owned a four-wheel drive vehicle?' (2 answers possible - Yes/No)
• If not: 'Have you ever investigated or seriously considered purchasing a 4 wheel drive vehicle?' (Yes / No).

The research company telephones random dialled numbers at the weekend, uses classification questions to ensure the sample reflects the known characteristics of the motoring population as a whole, identifies drivers and conducts interviews with 1,000 motorists.

These interviews might contain about 30 questions of which 10 are classification questions and the other 20 consist of small groups of questions such as those above, sponsored by individual clients.

The answers are entered directly into a computer during the interview. When all 1,000 are completed, the results are analysed and by Tuesday the client has been supplied with answers to his/her own questions, broken down according to the groups used in classification questions.

The overall charge is £350 per question plus £100 for various extra breakdowns of results by classification groups - the client pays £800 and has answers 6 days after deciding he/she needed the information. To conduct a separate survey would have cost far more and taken far longer because the client has effectively shared most of the costs of the survey with all the others who have sponsored questions - these include:

• design of the sample for the survey - decisions on who to interview to get a representative picture, etc...
• devising and asking classification questions
• executive time managing the survey
• most importantly, recruitment of 1,000 people prepared to answer questions.

In addition, the regular nature of the survey means that there are further economies of scale, research executives benefit from the experience of previous waves of the survey and the operation improves in efficiency as time goes on, at least in theory.

telephone

(usually CATI)

face-to-face

either in the street or in home, and either using pen and paper or CAPI technology

others

occasionally using post or the internet.